Method of treating ischemic states

ABSTRACT

The present invention relates to novel methods of use for known pharmacological anti-allergenic agents including disodiumchromoglycate (DSCG) and related compounds thereof, including generally bis chromones, benzopyrans, oxamic acids and salts or esters of each, preferably lodoxamide, its THAM salt and ethyl ester. All are subsequently included in the term biologues. The methods are for the treatment of pathological cardiovascular ischemic states in animals, particularly humans. Additionally, novel compositions incuding the biologues of the present invention in combination with known vasodilators and feed stuffs are also disclosed.

This application is a divisional application of application Ser. No.321,367, filed Nov. 16, 1981, now abandoned.

BACKGROUND OF THE INVENTION

The present invention relates to novel methods of using knownpharmacological agents in man. The invention further relates to novelcompositions employing these known pharmacological agents for thetreatment of various conditions or diseases in animals. Particularly,the present invention relates to the use of these known pharmacologicalagents in the treatment of pathological cardiovascular ischemic states(PACVIS) in animals and man.

The cardiovascular ischemic states whose treatment comprises the subjectmatter of the present invention are those states arising fromphysiological processes, particularly frankly pathological processes inwhich necrosis develops in smooth or striated muscles or skin.

The cardiovascular ischemic state, which leads to the development ofnecrosis in the cardiac muscle, includes, for example, angina,vasospastic angina, the sudden death syndrome, and the like. Theischemia resulting from these states is well known and is readilydiagnosed by an attending physical or veterinarian.

The cardiovascular ischemic states directly involving necrosis of smoothor striated muscle or skin include a wide variety of diseases andconditions. Further, certain cardiovascular ischemic states are arecognized untoward consequence of numerous other diseases andconditions.

One principle class of cardiovascular ischemic states is a consequenceof the various forms or types of vasospasms. Vasospasms refers to theabnormal spasm of the blood vessels, resulting in decrease in theircaliber. Ischemic in this invention refers to the condition of havinglocal and temporary deficiency of blood, due to the contraction of ablood vessel.

Although it is known that the pharmacological agents now found to beuseful in the treatment of pathological cardiovascular ischemic stateswere previously known for use as anti-allergenic agents, the mechanismfor such previously known use is not appreciated. It is known thathistamine plays a role in allergic reactions. Further this amine is apotent, easily released and functional endogenous compound in the body.For example, mast cells are the cells having granules in which histamineis highly concentrated. Histamine acts on two separate and distinctreceptors, termed H₁ and H₂ receptors. Both H₁ and H₂ receptors mediatethe vasodilator effects of histamine. Thus, the mast cells function inthe healthy vertebrate by the release of histamine. However, thespecific influences of the mast cell on ischemia is not well understood.For this reason, advantages of the present invention patentably extendmethods of treating pathological cardiovascular ischemic states(PACVIS). See Goth et al., "Histamine", Medical Pharmacology, chap. 15,pp. 177-188, 9th ed., C. V. Mosby Co., St. Louis, (1978).

Vasospasm is a condition common in adults and typically results in adeficiency of blood to muscle or skin which is then at risk ofdeveloping necrosis. Vasospasms typically result in numerous systematicmanifestations, characterized by ischemic disorders. Various types ofvasospasms associated with ischemia are known. See for example, TheMerck Manual, 13th edition, Merck, Sharp and Dohme ResearchLaboratories, Rahway, N.J. (1977). Among the types of vasospasms arethose which produce angina pectoris attributed to myocardial ischemia.These vasospasms may progress to myocardial infarction, attributable toischemic myocardial necrosis following an abrupt reduction in coronaryflow to a segment of the myocardium. Vascular spasm may also contributeto occlusion of the abdominal aorta and its branches, such as splanchnicartery occlusion, renal artery occlusion, or occlusion at thebifurcation, and peripheral vascular disorders consequent to occlusivearterial diseases. Other notable disease states whose principle longterm pathology arises from vasospasms as a constituent thereof includefunctional peripheral arterial disorders, such as Reynaud's phenomenon,acrocyanosis, and, rarely, erythromalagia. For example, Reynaud'sdisease may be idiopathic or secondary to such conditions as occlusivearterial disease. Likewise, such pathology may result from connectivetissue disorders; such as, progressive systemic sclerosis, neurogeniclesions, drug intoxication, dysproteinemias, myxedema, primary pulmonaryhypertension, and trauma. Much less severe in its ultimate effect is thecardiovascular ischemic state resulting from acrocyanosis.

Other disease conditions also induce pathological cardiovascularischemic states (PACVIS) with resulting untoward effects on the affectedanimal. For example, arterial embolism or thrombosis may be due to anumber of causes in an animal having a history of ischemia associatedwith vasospasms. Further, in many peripheral vascular diseases thevasospastic disorders induce pathological cardiovascular ischemic stateswith resulting pathological consequences.

Other vasospastic diseases also have the effect of inducing apathological cardiovascular ischemic state, for example, immersion foot,trench foot, herpes zoster, decubitous ulcers, and diabetic gangrene.

Finally, while many cardiovascular ischemic states have been attributedin the past to excess vasospasm, measuring the extent of ischemia is amore recent development. Consequently, limiting the extent of theischemia has likewise been difficult. For example, it has long beenknown in myocardial infarction that cardiac peformance after recoverydepends essentially on the mass of functioning muscle surviving theacute episode. Reinfarction or extension of infarct duringhospitalization is common. The use of increased inspired O₂concentration is one avenue of treatment. Recent animal studies suggestthat reduction of the O₂ requirements of myocardium and an increase incoronary perfusion or reduction of after load with vasodilators reducethe area of ischemic infarction. The primary effects may be based on thelowering of peripheral resistance. These observations need furtherevaluation but in selected patients, especially those with elevatedpressures, it appears to be appropriate in the acute stages ofinfarction to use vasodilators. These include such known agents asnitroglycerin, isosorbide dinitrate, trimethafan, or nitroprusside.

Measuring the ischemic myocardium at risk of necrosis is discussed byDeBoer et al. in "Autoradiographic Method for Measuring the IschemicMyocardium at Risk: Effects of Verapamil on Infarct size afterExperimental Coronary Artery Occlusion", Proc. Natl. Acad. Sci. U.S.A.,vol. 77, no. 10, pp. 6119-6123, October, 1980, Medical Sciences. Suchmeasurement in the investigation of pharmacological agents isadvantageous since myocardial infarct size appears to be a function ofischemia myocardium at risk of developing necrosis. Numerous methodshave been reported for assessing the effectiveness of pharmacologicalagents including by indirect methods. For example, one such reportindicates determination of epicardial enosis. See Kloner, R. A. et al.,Circulation, vol. 58, pp. 220-226 (1978). Another indirect method isdescribed as "Factors Influencing Infarct Size Following ExperimentalCoronary Artery Occlusions" by Maroko, P. R. et al., Circulation, vol.43, pp. 67-82 (January, 1971). Direct methods include postmorteminjection of dyes described by Reimer, K. A. et al. Lab. Invest., vol.40, pp. 633-644 (1979) or angiographic contrast agents described byJugdutt, B. I. et al., Circulation, vol. 60, pp. 1141-1150 (1979),Jugdutt, B. I. et al., Circulation, vol. 59, pp. 734-743 (1979),Hoffman, M. et al. Circulation, vol. 60, II-215A (ABSTR.) (1979).

An efficient means of assessing the inhibition of cardiovascularischemic states by a chemical agent is described by DeBoer et al., citedabove. The method of DeBoer et al. determines the ability of a chemicalagent to affect infarct size. The first objective of this study is todetermine the physiological status of coronary blood flood after thecoronary arterial occlusion but prior to the administration of drugs.The second objective of this study is to use autoradioagraphy to testthe efficacy of delayed administration of the drug, in this caseverapamil, in reducing myocardiam infarction size.

The technique of DeBoer et al. for measuring the reduction of myocardialinfarct size employs the techniques described in the above noted DeBoeret al. article. Thirty minutes after left anterior decending coronaryocclusion mongrel dogs are randomized into control or treatment groups.Ischemic bed size (area at risk) is determined both before treatment bythe injection of 99m Tc labeled albumin microspheres with postmortemautoradioagraphy (AR-R) and during treatment by left atrial dyeinjection immediately before sacrifice (AR-D). Infarct size (IS) isdetermined six hours after coronary arterial occlusion by triphenyltetrazolium staining and expressed as percent of left ventrical beforeocclusion.

In summary, the compounds of this invention are substituted in theDeBoer et al. techniques. By measuring their inhibition of the ischemicstate, it is understood that the spread of necrosis is likewiseinhibited which consequently reduces the size of the infarctionfollowing a coronary occlusion.

It is by this method that the efficacy of the known compounds areevaluated for the instant invention.

The known compounds employed in the novel methods and compositionsdisclosed herein are previously known as anti-allergenic agentsspecifically including disodiumchromoglycate (DSCG) and DSCGanti-allergenic biologues. Hereinafter DSCG and DSCG anti-allergenicbiologues are referred to in the invention by the term "biologues."These biologues include anti-allergenic bis chromones related to DSCG.Both DSCG and bis chromones related to DSCG are described in U.S. Pat.No. 3,419,578. Further related anti-allergenic bis chromones are thosedescribed in U.S. Pat. Nos. 3,519,652 and 3,673,218. Moreover,additional compounds of the invention biologues, includinganti-allergenic uses therefore, are described in U.S. Pat. No.4,046,910, issued Sept. 6, 1977. The description of DSCG and relatedanti-allergenic bis chromones which are the biologues of the presentinvention and their anti-allergenic compositions are incorporated hereby reference from U.S. Pat. Nos. 3,419,578, 3,519,652, 3,673,218, and4,046,910.

Another class of compounds within the biologues of the present inventionare the anti-allergenic benzopyrans, particularly the compoundsdescribed in U.S. Pat. Nos. 4,159,273, 3,786,071, 3,952,104, and4,055,654. Notable among these compounds is proxicromil (FPL 57,787),6,7,8,9-tetrahydro-5'-hydroxy-4-oxo-10-propyl-4H-naphtho[2,3-b]pyran-2--carboxylicacid, described in Example 8 of U.S. Pat. No. 4,159,273. The descriptionand anti-allergenic compositions of these anti-allergenic benzopyransare incorporated here by reference from U.S. Pat. Nos. 4,159,273,3,786,071, 4,055,654, and 3,952,104.

Yet, another class of compounds within the biologues of the presentinvention are the anti-allergenic oxamic acids or derivatives thereof.These compounds, together with their anti-allergenic uses andcompositions, are described in U.S. Pat. Nos. 3,993,679, 4,159,278,4,095,028, 4,089,973, 4,011,337, 4,091,011, 3,972,911, 4,067,995,3,980,660, 4,044,148, 3,982,006, 4,061,791, 4,017,538, 4,119,783,4,113,880, 4,128,660, 4,150,140, 3,966,965, 3,963,660, 4,038,398,3,987,192, 3,852,324, and 3,836,541. The preparations of such compoundsand their anti-allergenic compositions are incorporated by referencehere from the aforementioned United States patents. The most preferredbiologue in the present invention is the dioxamateN,N'-(2-chloro-5-cyano-m-phenylene)dioxamic acid (lodoxamide). Amonglodoxamides preferred forms are the bis THAM, (tris(hydroxymethyl)-aminomethane) salt and the diethyl ester, particularly the diethyl ester.

PRIOR ART

DSCG and its anti-allergenic biologues and anti-allergenic uses,therefore, are known in the art. See the various United States patentscited above. Additionally, see copending U.S. application Ser. No.168,827, filed July 10, 1980, which is a continuation-in-part of Ser.No. 073,394, filed Sept. 7, 1979 and Ser. No. 073,400, filed Sept. 7,1979, for disclosure of further utility as agents for the treatment ofpathological mineral resorptive states of the DSCG and anti-allergenicbiologues of this invention. Further known are numerous vasodilatingagents. See Goth et al., Medical Pharmacology, "Coronary Vasodilators",9th ed., pp. 408-413, The C. V. Mosby Company, St. Louis, Mo. (1978),for examples of such agents.

With respect to DSCG, this agent has been reported to inhibit mast celldegranulation of monkey gingiva. See Nuki, K. et al., "The Inhibition ofMast Cell Degranulation In Monkey Gingiva by Disodium Cromoglycate", J.Periodontal. Res. 10:282-287 (1975) and references cited therein. Tworeferences of particular interest cited therein are Goldhaber, P.,"Heparin Enhancement of Factors Stimulating Bone Resorption in TissueCulture", Science 147:407-408 (1965), and Shapiro, S. et al., "Mast CellPopulation in Gingiva Affected by Chronic Destructive PeriodontalDisease", Periodontics 40:276-278 (1969).

SUMMARY OF THE INVENTION

The present invention particularly provides:

(1) A method of arresting or preventing a pathological cardiovascularischemic state (PACVIS) in an animal exhibiting or susceptible to thedevelopment of said PACVIS which comprises:

systemically administering to said animal an amount of an anti-PACVISbiologue effective to treat or prevent said PACVIS;

(2) In a method of preventing or treating a pathological cardiovascularischemic state (PACVIS) with one or more known vasodilating agentscomprising coronary vasodilators such as nitroglycerin, isosorbidedinitrate, or direct vasodilators such as trimethafan or nitroprusside,the improvement which comprises:

concomitantly administering an amount of an anti-PACVIS biologue whichtogether with said known vasodilator agent or agents is effective toprevent or arrest said PACVIS;

(3) In a unit dose of a pharmaceutical composition for preventing ortreating a pathological cardiovascular ischemic state (PACVIS) with oneor more known coronary or direct vasodilating agents comprisingnitroglycerin, isosorbide dinitrate, trimethafan, or nitroprusside, theimprovement which comprises:

an amount of anti-PACVIS biologue which together with said knownvasodilating agent or agents is an effective unit dose to prevent orarrest said PACVIS;

(4) an animal feed for feeding to an animal suffering from orsusceptible to the development of a pathological cardiovascular ischemicstate (PACVIS) which comprises:

an anti-PACVIS biologue in a concentration such that an amount thereofwhich will be injested by the animal over a predetermined intervalcontains an amount of said anti-PACVIS biologue effective to arrest orprevent said PACVIS during said predetermined interval;

(5) A feed premix for preparing an animal feed for feeding to an animalsuffering from or susceptible to the development of a pathologicalcardiovascular ischemic state (PACVIS) which comprises:

an anti-PACVIS biologue in a concentration such that when said animalfeed premix is diluted with animal feed an amount thereof which will beinjested in a predetermined interval contains an amount of saidanti-PACVIS biologue effective to arrest or prevent said PACVIS duringsaid predetermined interval.

The methods or compositions of the present invention is especiallypreferred to treat humans for limiting infarct size following a coronaryocclusion.

The present invention relates to the treatment of animals, althoughmammals represent particularly preferred embodiments of the presentinvention. Most preferred is the treatment of humans by the instantmethod. The present invention thus provides a method of treating bothhumans and valuable domestic mammals such as bovine, equine, canine, andfeline species, and chickens, turkeys, geese, ducks, and other fowl.

The present invention relates to the arrest or prophylaxis ofpathological cardiovascular ischemic states or of "PACVIS". Theemployment of sound medical therapy requires that the anti-PACVIS agentbe employed prophylactically only in cases where the animal or patientis particularly susceptible to the development of PACVIS. The conditionsand circumstances which increase susceptibility are readily ascertainedto the ordinarily skilled physician or veterinarian and include:

(1) Coronary vasospasm which includes angina pectoris, vasospasmicangina, myocardial infarction;

(2) Peripheral vasospasm in peripheral vascular diseases which includesReynaud's phenomen, mesenteric ischemia, "hepatorenal syndrome";

(3) Cerebral vasospasm;

(4) A diagnosis of any disease or condition in which a PACVIS is apotential consequence such as from arrhythmic diseases.

In the prophylactic use of these anti-PACVIS agents, the dose effectivefor the prevention of the PACVIS is determined by patient or animalresponse, as discussed hereinafter for therapeutic uses, and is, ingeneral, somewhat less than the dose required to treat a PACVIS.

A PACVIS which is arrested or prevented in accordance with the presentinvention includes each of the various states or conditions describedabove where the long-term effects on the animal are untoward, and hencethe condition or state is associated with a direct or indirectpathological process.

A PACVIS is not an uncommon condition encountered in medical orveterinary practice. Accordingly, the diagnosis of a PACVIS is readilyundertaken by the ordinarily skilled physician or veterinarian.

The dose regimen for the anti-PACVIS biologue employed is selected inaccordance with a variety of factors, including the type, age, weight,sex, and medical condition of the mammal, the severity of PACVIS and itsduration, and the particular anti-PACVIS biologue being administered. Anordinarily skilled physician or veterinarian, subsequent to thediagnosis of a PACVIS, will readily determine and describe the effectiveamount of the anti-PACVIS biologue to arrest the progress of thecondition. In so proceeding, the physician or veterinarian would, forexample, employ relatively low dosages of the anti-PACVIS biologue,subsequently increasing dose until a maximum response was obtained. Sucha response is obtained when the ischemia begins to decrease andsubsequently substantially ceases, or at a minimum remains much reduced.

The anti-PACVIS biologues are the various anti-allergenic agents knownin the art as discussed above. Such substances include DSCG, otheranti-allergenic bis chromones, anti-allergenic benzopyrans andpreferably anti-allergenic oxamic acids or derivatives (oxamates).

Various formulations may be employed including nasal drops, oral hardfilled capsules, nebulized aerosols, interdermal patches, or intravenousdosages. Routes of administration include oral, insufflation,intranasal, intrabronchial, subcutaneous and intravenous; oral andinsufflation being preferred.

When DSCG is employed as the anti-PACVIS biologue the compound is mostpreferably administered either intranasally or by insufflation. Thedosage may be 5-400 mg per patient per dose but preferably is about 20mg. Dosages administered through the nasal route are by sterile solutionof from 1/2 percent to 10 percent concentration with approximately 2percent concentration preferred. Equivalent parental or oral dosages canalso be administered. When dosages significantly higher than 20 mg perpatient particularly by insufflation are employed, the systemic toxicityof DSCG must be carefully evaluated and subsequent dosages determined byevaluating the benefit of the drug in relation to any such toxicmanifestations.

For anti-PACVIS bis chromones routes of administration which may beemployed include intranasal, insufflation, oral, interdermal or as aninjectable both intramuscular and intravenous. Effective dosageequivalent to the DSCG dose above may be determined and employed asdescribed above. Initial dosages of anti-PACVIS oxamate or benzopyranmay be determined by administering minimum dosages and subsequentlyevaluating increasing dosages determined by the benefit of the drug inrelation to toxic manifestations thereof.

The preferred oxamate, lodoxamide, described above provides aparticularly efficacious result when administered rectally,intranasally, by insufflation, orally, intradermally or as aninjectable. The dosage range for insufflation (aerosol), rectal,intranasal or intradermal administration is from 0.0001 mg/dose to 20mg/dose. These routes of administration have a preferred dosage range offrom 0.01 mg/dose to 10 mg/dose. Oral dosage ranges for the preferredTHAM salt of lodoxamide is from 0.1 mg/dose to 100 mg/dose. The diethylester of lodoxamide is preferably administered by the oral route at adosage range of from 0.5 mg/dose to 30 mg/dose. Finally, the dosagerange for injectable oxamates is from 0.0001 mg/dose to 5 mg/dose,preferably 0.001 mg/dose to 1 mg/dose. When dosages of above 5 mg perpatient per dose orally are employed, the systemic toxicity of theanti-PACVIS oxamate or benzopyran must be carefully evaluated andsubsequent dosages determined by evaluating the benefit of the biologuein relation to any such toxic manifestations.

In order to obtain the efficacious result provided by the presentinvention, a route of administration permitting systemic action may berequired, as indicated above. Where localized effects are exerted byabsorption, topical applications may be especially preferred. Thus, inthe treatment of a PACVIS secondary to myocardial infarction, liquids orgels or viscous fluids may be preferred vehicles when applied to theappropriate localized chest area.

Generally, for anti-PACVIS biologues known to be orally active the oralroute of administration is preferred.

Parenteral routes of administration provide the desired activity at theappropriate equivalent dose, as described above. Thus, the presentmethod provides intravenous injection or infusion and subcutaneousinjection. Regardless of the route of administration selected, theanti-PACVIS biologue is formulated into pharmaceutically acceptibledosage forms by conventional methods known to the pharmaceutical art.

When powders, pastes or gels are required, the anti-PACVIS biologue isconveniently formulated by mixture into conventional compositions. Inthe case of parenteral administration, sterile solutions for injectionor infusion are prepared in accordance with readily availabletechniques. Similar sterile solutions are used for compositions in nasaladministration.

The various carboxyl containing anti-PACVIS agents are all employed inany conventional, pharmaceutically acceptable form. Thus, these agentsare optionally employed as free acids, esters, or salts.

The use of the anti-PACVIS biologue is, by a further embodiment of thepresent invention, undertaken concomitantly with other forms ofconventional therapy for a PACVIS. Such other forms of conventionaltherapy include, for example, the various chemical therapies describedin Goth et al., cited above. When such combination therapies areemployed, significant anti-PACVIS effects are often obtained withreduced effective dosages of the anti-PACVIS biologue agent employedherein.

In accordance with this further embodiment of the present invention,there are provided novel pharmaceutical compositions for anti-PACVIStherapy. These novel compositions consist of combinations of two or moreactive agents, one such agent being an instant anti-PACVIS biologue, andthe second and further agents being the heretofore known agents havingthe vasodilating effect. Such previously known vasodilating agentsinclude those known as adrenergic vasodilators, direct vasodilators, andcoronary vasodilators. Adrenergic vasodilators include known medicamentssuch as nylidrin, isoxsuprine, and isoproterenol. Direct vasodilatorsinclude other known medicaments such as hydralazine, diazoxide,minoxidil, and sodium nitroprusside. Additionally, the anti-PACVISbiologues may be combined with α or β adrenergic blocking drugs. SeeGoth et al. supra, pp. 89-114. The α adrenergic blocking drugs include,for example, prazosin and β adrenergic blocking drugs includepropranolol. Such novel compositions are advantageously used inarresting a PACVIS, often permitting a reduced dosage of the instantanti-PACVIS agent than that which would be required were it the soletherapy for arresting or preventing the PACVIS.

In these novel pharmaceutical compositions, the instant anti-PACVISbiologue is employed for each unit dosage in an amount equal to theamount of the instant anti-PACVIS biologue were it the sole therapy downto an amount not less than 50 percent thereof. The other conventionalanti-PACVIS agent or agents are present therein at the known amountsemployed in the treatment to accomplish vasodilation.

Moreover, the present invention further provides compositions of theinstant anti-PACVIS biologues exhibiting extraordinary convenience as aresult of the topical activity of these agents in the treatment ofPACVIS. Employed in these novel powder, paste, cream, or gelcompositions are conventional ingredients to obtain the desiredconstituency of each composition except for the anti-PACVIS biologue.

Such powders, pastes, creams, or gels contain an effective amount of theanti-PACVIS biologue such that an application of a predeterminedquantity of the powders, pastes, or gels to the localized area result inthe desired anti-PACVIS effect. Such powders, pastes, or gels areformulated by conventional means as is known in the art, andparticularly include the combination of an instant anti-PACVIS biologuewith a conventional carrier (for example, powders: lactose, magnesiumstearate, starch, talc; paste: stearic acid, glyceryl monostearate, coldcream; gel: polyoxethylene glycol; creams: spermacet, cetyl alcohol,stearic acid.) Such powders, pastes, creams or gels are particularlyuseful in the topical treatment of PACVIS secondary to functionalperipheral diseases as described above.

Similarly, the instant invention relates to the further liquidcomposition comprising the anti-PACVIS biologue in solutions adapted fornasal administration. In accordance with such novel compositions, theinstant anti-PACVIS biologue is present in the conventional sterilesolution at a concentration such that a predetermined volume of theadministered drops or aerosol contains an amount of the anti-PACVISbiologue effective to exert the desired anti-PACVIS effect on contactwith the nasal tissues.

Foregoing novel compositions are preferably provided in unit dosage orpackage dosage forms, where the composition consists of an amount ofeach pharmacological agent required for a single dose or a predeterminedseries of doses over some predetermined interval of time. Forcombination therapies such unit or package dosages, therefore, mayconsist of a single pharmaceutical entity, containing therewithin bothagents or a paired or otherwise ordered series of such discrete entitiescontaining these agents seperately. Hence, within the ambit of the novelpharmaceutical compositions provided herein are those which wouldinclude packages containing a multiplicity of discrete pharmaceuticalentities in an ordered way for the administration of these novelcompositions over a predetermined period of time. For example, by apreferred embodiment of the present invention such novel compositionswould include discrete pharmaceutical entities containing lesser orgreater amounts of the novel anti-PACVIS biologue at the time therapy isinitiated with gradually increasing or decreasing amounts of the instantanti-PACVIS biologue in discrete pharmaceutical entities intended foradministration subsequently as therapy progresses.

Finally, for the anti-PACVIS biologues indicated above as orally active,there are provided in accordance with the present invention feeds andfeed premixes containing amounts of the instant anti-PACVIS biologuewhich, when present in the animal's feed, is at a concentrationeffective to exert the desired anti-PACVIS effect. Such feed and feedpremixes are made in accordance with readily known and availabletechniques particularly useful in the treatment of animals where thePACVIS compromise the animal's value. Examples of a PACVIS whichcompromises the value of an animal include heartworm disease in dogs andaneurysms in turkeys.

Thus, the method provided by the present invention provides for thesystemic administration to an animal in an amount of an anti-PACVISagent effective to arrest or prevent a PACVIS. The anti-PACVIS agentcontemplated for use in the present invention feeds and feed premixesare those compounds known in the prior art and described in theaforementioned U.S. patents.

Examples of preferred anti-PACVIS bis chromones are genericallyrepresented by formula I,

wherein R₁, R₂, R₃, R₄, R₅, and R₆ are hydrogen, halogen (chloro, bromo,or iodo), lower alkyl (preferably alkyl of one to four carbon atoms,inclusive), hydroxy, or lower alkoxy (preferably alkoxy of one to fourcarbon atoms, inclusive);

wherein X is straight or branched chain polymethylene of three to sevencarbon atoms, inclusive, --CH₂ --CH═CH--CH₂ --, --CH₂ --CH₂ --O--CH₂--CH₂ --, --CH₂ --CO--CH₂ --, --CH₂ --(o--Ph)--CH₂ ;

wherein o--Ph is 1,2--phenylene, --CH₂ --C(CH₂ OH) (CH₂ Cl)--CH₂ --,--CH₂ --CH(OH)--CH₂ --, or --CH₂ --CH(OH)--CH₂ --O--CH₂ --CH(OH)--CH₂--; and the salts, esters, and amides thereof.

Preferred as anti-PAVCIS bis chromones in accordance with the presentinvention are DSCG and the various other salt and ester forms thereof,which compounds are incorporated here by reference from U.S. Pat. No.3,419,578.

Preferred among the anti-PACVIS oxamates are the oxanilic acidderivatives represented by formula II and the phenylene dioxamic acidderivatives represented by formula III;

wherein R₁ is hydrogen, a pharmacologically acceptable cation or alkyl,preferably alkyl of one to 12 carbon atoms, inclusive;

wherein one of R₂, R₃, R₄, R₅, and R₆ is hydrogen or cyano;

wherein a second and a third of R₂, R₃, R₄, R₅, and R₆ are selected fromthe group consisting of hydrogen, nitro, amino, halo (fluoro, chloro,bromo, or iodo), alkyl (preferably alkyl of one to four carbon atoms,inclusive), hydroxy, alkoxy (preferably alkoxy of one to four carbonatoms, inclusive), and trifluoromethyl being the same or different, and

wherein the remainder of R₂, R₃, R₄, R₅, R₆ are hydrogen. Moreparticularly those compounds of formulas II and III wherein R₁ is ethylor protonated trimethamine and R₃ is cyano and R₆ (II) or R₅ (III) ischloro, the other variables being hydrogen are preferred.

The present invention thus provides a surprising and unexpected methodof use and unexpectedly convenient and efficacious compositions ofmatter for a class of pharmacological agents previously known to beuseful for unrelated pharmaceutical and other purposes.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The advantageous effects of anti-PACVIS biologues in accordance with thepresent invention are demonstrated by the experimental results, reportedhereinafter, which are illustrative (but not limiting) as to theoperation of the novel methods described above.

EXAMPLE I

The reduction of myocardial infarct size as measured by the effects oninfarct size after experimental coronary artery occlusion of lodoxamide,N,N'-(2-chloro-5-cyano-n-phenylene)dioxamic acid, (as itsbis-tris(hydroxymethyl)aminomethane salt).

Following the procedure of DeBoer, W. E. et al., Proc. Natl. Acad. Sci.U.S.A., vol. 77, no. 10, pp. 6119-6123 (October, 1980) Medical Sciences,the anti-PACVIS activity of lodoxamide is assessed. The followingexperiment is undertaken.

Twenty-two barbiturate anesthetized dogs are treated to receive highleft anterior descending coronary artery occlusions. Ischemic bed sizeor area at risk of developing necrosis (AR-R) is determined beforetreatment by injection of 99m Tc labeled albumin microspheres withpost-mortem autoradiography. The ischemic zone appears as a cold spotimage. A second area at risk is determined at the time of sacrifice(AR-D) by use of an in vivo left atrial injection of thioflavin S (afluorescent dye which stains myocardium receiving flow yellow-green, butdoes not stain ischemic tissue). Infarct size (IS) is determined sixhours after coronary occlusion by triphenyltetrazolium staining of 5 mmtransverse slices of the left ventricle. Thirty minutes after leftanterior descending coronary occlusion, animals are randomized tocontrols (12 dogs receiving 0.9 percent saline I.V.) or lodoxamide,N,N'-(2-chloro-5-cyano-n-phenylene)dioxamic acid, (as itsbis-tris-(hydroxymethyl)aminomethane salt) therapy (10 dogs receiving 20mg per kg per hour by continuous I.V. drip). AR-R, AR-D, and IS areexpressed as percentage of the left ventricle before occlusion. Infarctsize is also expressed as a percentage of the area at risk. The resultsare shown in the table below.

                  TABLE I    ______________________________________                        Lodoxamide           Controls     THAM Salt  P    ______________________________________    AR-R     28.7 + 2.6     25.3 + 3.7 NS    AR-D     28.9 + 2.5     25.2 + 3.1 NS    IS       30.0 + 2.7     13.8 + 3.2 .002    IS/AR-R  104.5 + 3.8     54.5 + 11.0                                       .001    IS/AR-D  103.8 + 3.4    54.8 + 8.2 .001    ______________________________________

The results of Table I indicate the oxamate, lodoxamide induces asignificant protective action on ischemic myocardium by showing asignificant reduction in infarct size.

A further experiment indicates the prevention of necrosis by theoxamate, lodoxamide in a prophylactic manner in a manner similar toExample I.

EXAMPLE II

Fourteen dogs are treated to receive occlusion of the proximal leftcircumflex coronary artery. Ischemic bed size or area at risk ofdeveloping necrosis (AR-R) is determined before treatment by injectionof 99m Tc labeled albumin microspheres with postmortem autoradiography.A second area at risk is determined at the time of sacrifice (AR-D) byuse of an in vivo left atrial injection of thioflavin S (a fluorescentdye which stains myocardium receiving flow yellow-green, but does notstain ischemic tissue) in a manner similar to Example I. The animals arerandomized to controls (9 dogs) or lodoxamide therapy (8 dogs receiving20 mg/kg/hour times two infused I.V. during the period starting 30minutes prior to and throughout 90 minutes of complete occlusion,followed by reperfusion). Infarct size (IS) is determined 24 hours afterthe 90 minute occlusion-reperfusion. The results are shown below in amanner similar to that described for Example I. In other words, thefollowing Table II shows infarct size determined as a percent of thearea at risk or as a percent of the total left ventricle.

                  TABLE II    ______________________________________                      Lodoxamide    Control           THAM Salt  P    ______________________________________    AR-R    45.3 + 2.8    22.8 + 2.8 0.001    AR-D    42.8 + 1.7    43.1 + 3.6 NS    IS      19.5 + 1.5     9.7 + 1.0 0.001    ______________________________________

The results in Table II show the oxamide therapy occasions a decrease ininfarct size.

I claim:
 1. In a method of preventing or treating a pathologicalcardiovascular ischemic state (PACVIS) in an animal exhibiting orsusceptible to development of said PACVIS with one or more knownvasodilating agents selected from the group consisting of coronaryvasodilating agents including nitroglycerin and isosorbide dinitrate,and direct vasodilating agents including hydralazine, diazoxide,minoxidil, and sodium nitroprusside, the improvement which comprises:concomitantly administering an amount of an anti-PACVIS biologue equalto the amount of the instant anti-PACVIS biologue were it the soletherapy, down to an amount not less than 50 percent thereof, which,together with said known vasodilator agent, is effective to prevent orarrest said PACVIS.
 2. A pharmaceutical composition in a unit dose form,for preventing or treating a pathological cardiovascular ischemic state(PACVIS) comprising one or more known coronary or direct vasodilatingagents and:an amount of an anti-PACVIS biologue equal to the amount ofthe instant anti-PACVIS biologue were it the sole therapy, down to anamount not less than 50 percent thereof, which, together with said knownvasodilating agent or agents, in an effective unit dose to prevent orarrest said PACVIS.